Meta

Month: December 2012

The outlook for the world in terms of energy security and global warming seems pretty bleak. But I think there’s a light on the horizon, and that light is the sun. Amongst all the renewable energy areas, solar seems to me to be the only one with exponential characteristics (cost reductions, adoption), and the only one that can tap the consumer capital (trillions/year in the US alone).

I thought I’d have a go at quantifying the picture. This is fairly BOTE stuff, but still interesting. Note also that I’m not saying Solar is definitely what we are going to do, but that if we do nothing else, we will do solar.

The technium wants more power, a lot more power. Fossil is not going to do the job from here on out. So a renewable buildout will happen, and it’ll blow what we have now out of the water. Our future is not energy poor.

He says, amongst other things, that for us to stabilize at 2 degrees C temperature rise, we need to move entirely to renewables over the next 25 years.

We use 18 TW of power on the earth at the moment. He’d like us to actually reduce our power usage, but I’d say we’d have to plan to do about double that, at least.

In energy terms, 18TW is about 155,880TWh / year. So we need to hit a target of roughly 300,000TWh / year globally from renewables (and no fossil) by about 2037. That’s about 34TW.

There’s a lot of talk about solar installation going exponential. Gregor McDonald shows a graph that looks exponential (he says parabolic, not sure why) showing an improvement rate conservatively of 1.6 increase / year in total global solar installation, and some specific figures; eg: in 2011, the total world solar output was 55.7 TWh. Small.

But if we extrapolate using an increase of 1.6/year (factor of 10 every 5 years), we get this:

Year Global Solar TW
2010 0.00 – so small it rounded to zero)
2015 0.04 – looking grim
2020 0.44 – still pretty grim
2025 4.58 – more than current world electrical power of 2 TW
2030 48.04 – more than the 34 TW we need before 2037
2035 503.77 – a stupendous renewable power output, a golden age on earth
2040 5,282.39 – impossible to understand the implications of this, but maybe also we can’t get here.

85,000 TW (see Saul’s slides above) is the cap of all the solar that hits the earth. Something less than this is what we can harvest. Let’s say we can cover 10% of the earth with 10% efficient solar, that’s 850TW. I expect the efficiency will get higher; we can’t expect that what we build out in the 2030s will be as poor as what we use now. So maybe we can go further? Even if we can’t, these are very, very large numbers! Probably enough to get us off planet easily, collecting power in space (the earth doesn’t actually trap very much of the output of the sun!).

So basically this progression will look tragically awful until the early 2020s, when it’ll start looking promising, then we switch entirely to solar, then shortly after that energy becomes totally abundant; what on earth would we do with it all???